如何在Rails模型中指定关联的紧急加载 [英] How to specify eager loading of associations in rails model

问题描述

class A < ActiveRecord::Base
  has_many :Bs
  has_many :Cs
  ...
end

我希望在每次对A进行查询时都加载所有B和C，例如 A.where（name：：abc），

I wish to load all of B's and C's whenever I do a query on A, say A.where(name: :abc), with a single query, instead of multiple calls to database.

我不希望为 .includes 指定一个查询我运行的每个查询。我如何在模型本身中指定急切的加载？

I don't wish to specify .includes for every query I run. How do I specify eager loading in the model itself?

我看了很多类似的问题，并尝试这样做，但不起作用：

I looked many similar question and tried do this but it does not work:

default_scope :include => [:Bs, :Cs]

推荐答案

default_scope {includes（：Bs，：Cs）} 应该这样做。

据我所知，作用域采用一个块作为参数不是选项的哈希。我只是在Rails控制台中尝试过，似乎可以正常工作。

As far as I know the scope takes a block as argument not a hash of options. I just tried it in the rails console and seems to work.

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